External slashing protection (#5895)

* slasher grpc client

* do not export

* slasher on a different package

* fix featureconfig

* change to rough time

* revert roughtime

* remove extra comma

* revert order change

* goimports

* fix comments and tests

* fix package name

* revert reorder

* comment for start

* service

* fix visibility

* external slasher validator protection implementation

* gaz

* fix comment

* add comments

* nishant feedback

* raul feedback

* preston feedback

* fix flags

* fix imports

* fix imports

* port 4002

* added tests

* fix log

* fix imports

* fix imports name

* raul feedback

* gaz

* terence comment

* change name

* runtime fixes

* add flag check

Co-authored-by: prylabs-bulldozer[bot] <58059840+prylabs-bulldozer[bot]@users.noreply.github.com>

nogo_config.json

@@ -73,7 +73,7 @@
       "beacon-chain/blockchain/testing/*": "Test-only package",
       "beacon-chain/p2p/sender\\.go": "Libp2p uses time.Now and this file sets a time based deadline in such a way that roughtime cannot be used",
       "beacon-chain/sync/deadlines\\.go": "Libp2p uses time.Now and this file sets a time based deadline in such a way that roughtime cannot be used",
-      "validator/client/grpc_interceptor\\.go": "Uses time.Now() for gRPC duration logging"
+      "shared/grpcutils/grpcutils\\.go": "Uses time.Now() for gRPC duration logging"
     }
   },
   "errcheck": {